Glucose 6-phosphate dehydrogenase from sweet potato

摘要

Glucose 6-phosphate dehydrogenase was purified about 290-fold from sweet potato root tissue. The molecular weight was estimated to be 110,000 by Bio-Gel 300 column chromatography. A LINEWEAVER-BURK plot of the reciprocal rate against reciprocal glucose 6-phosphate concentration was concave downwards. A HILL coefficient less than 1 was obtained at lower concentrations of glucose 6-phosphate (below 0.5 mM). These results suggest that binding of glucose 6-phosphate to the enzyme occurs with negative cooperativity.